While Electronic Health Records (EHR) systems have been consistently promoted as a policy priority for improving the quality and efficiency of the American healthcare system, there is limited research evidence to inform policy-makers about the effects of EHR use on care coordination. This study will use a quasi- experimental design with concurrent controls to evaluate the impact of outpatient physician use of a newly implemented, certified EHR system in Kaiser Permanente Northern California (KPNC) on measures of care coordination, and in turn the association between care coordination and care quality for patients receiving care from multiple clinicians. The study includes all 110 primary care teams in 18 medical centers within the KPNC delivery system, which served over 2 million adult patients (age 18+) between 2005 and 2008. Using multivariate regression analysis, I will examine the association between EHR use and care coordination, while adjusting for clinician characteristics and organizational factors. Additionally, I will examine whether the association between EHR use and care coordination varies by team climate. Finally, I will assess the association between care coordination and clinical care. Measures of care coordination and team climate will be captured using existing self-administered survey responses collected from primary care clinicians in 2005, 2006, and 2008 during the staggered implementation of the EHR system. Quality and clinical outcome measures will be captured using the health system's automated databases and will include guideline-adherent prescription drug use and laboratory monitoring, and physiologic disease control (measured by laboratory tests) for diabetes patients receiving care from multiple clinicians. This study leverages existing data, including survey responses that capture detailed measures of clinician reported care coordination and team climate at multiple points in time as well as the substantial data resources from the study setting. In addition, the staggered nature of the EHR implementation allows for adjustment of secular changes. The 2009 stimulus bill allocated billions of dollars to promote the adoption and meaningful use of EHR. In fact, the definition of meaningful use was specifically designed to target care coordination and care quality. This study will provide important evidence on the role of EHR use on care coordination and quality improvement that are broadly applicable across the nation. In the current clinical environment, where care provided to patients is increasingly fragmented, and also increasingly complex, effective care coordination is essential. Health Information Technology, and specifically EHR, offer new opportunities for improving overall quality of care, preventing medical errors, and reducing health care costs. PUBLIC HEALTH RELEVANCE: The aim of this study is to evaluate the impact of Electronic Health Records (EHR) use on clinician reported measures of care coordination, and in turn the association between care coordination and clinical care for patients with complex care needs. This study will provide important evidence on the role of EHR use on care coordination and quality improvement that are broadly applicable across the nation. In the current clinical environment, where care provided to patients is increasingly fragmented, and also increasingly complex, effective care coordination is essential.